Linkerd Edge Release Roundup: November 2024

Welcome to the November 2024 Edge Release Roundup post, where we dive into the most recent edge releases to help keep everyone up to date on the latest and greatest! This month’s Roundup is a little late due to KubeCon – we’ll cover the October edge releases here, then pick up again in early December to tackle the flood of November edge releases that take us up to Linkerd 2.17!

How to give feedback

Edge releases are a snapshot of our current development work on main; by definition, they always have the most recent features but they may have incomplete features, features that end up getting rolled back later, or (like all software) even bugs. That said, edge releases are intended for production use, and go through a rigorous set of automated and manual tests before being released.

We would be delighted to hear how these releases work out for you! You can open a GitHub issue or discussion, join us on Slack, or visit the Buoyant Linkerd Forum – all are great ways to reach us.

Community contributions

We couldn’t do what we do without the Linkerd community, and this batch of releases is definitely no exception. Huge thanks to Aran Shavit, Vadim Makerov, and @patest-dev for their contributions! You’ll find more information about all of these contributions in the release-by-release details below.

Recommendations and breaking changes

All these releases are recommended for general use. There is one breaking change, but it’s a good breaking change: starting in edge-24.10.5, a gRPC request that hits a timeout will correctly return a DEADLINE-EXCEEDED gRPC status rather than an UNAVAILABLE gRPC status. This is the way it really should’ve always been, but it’s still a breaking change.

Additionally, if you’re using Linkerd multicluster, you’ll probably be best off jumping straight to edge-24.10.3 or later: edge-24.9.3 introduced a change to the Link CRD that’s not compatible with previous versions, and that situation isn’t fully resolved until edge-24.10.3.

The releases

October’s releases are mostly cleaning up a few things before the final push for Linkerd 2.17 in November, but there are a couple of new features here as well! Of course, each edge release includes many dependency updates which we won’t list here, but you can find them in the release notes for each release.

edge-24.10.5 (October 31, 2024)

edge-24.10.5 contains the only breaking change in the October releases: as of this release, a gRPC request that hits a timeout will correctly return a a DEADLINE-EXCEEDED gRPC status, rather than returning an UNAVAILABLE gRPC status as in previous releases. This fix allows gRPC clients to properly distinguish between a timeout and other errors, so it’s an important change.

edge-24.10.4 (October 24, 2024)

edge-24.10.4 stops using automountServiceAccountToken, switching instead to using explicitly-configured projected volumes for the ServiceAccountTokens we need, helping Linkerd comply with current best practices around Kubernetes security (thanks, Aran Shavit!). Additionally, this release updates the deprecation text for v1beta1 of the Server CRD; anyone using that version should go ahead and upgrade to Server v1beta3 (thanks, @patest-dev!).

edge-24.10.3 (October 17, 2024)

edge-24.10.3 improves outbound HTTP and gRPC metrics by adding hostname and zone_locality labels, providing the hostname and zone used for the target. It also improves distributed tracing by allowing configuring the service name for Linkerd’s distributed traces (fixing #11157) and by fixing a bug where the linkerd-jaeger injector could mistakenly alter annotations it shouldn’t have.

This release also fixes a bug where the CNI plugin would silently fail if the underlying Node hit the inotify limit – the plugin will now catch the error and crash, which will surface the problem so the cluster operators notice it and fix it. Finally, edge-24.10.3 fully fixes linkerd multicluster link so that it produces YAML that can be applied into clusters running versions prior to edge-24.9.3.

edge-24.10.2 (October 10, 2024)

If you’re using Linkerd multicluster, you should consider going straight to edge-24.10.3 to avoid compatibility issues with clusters running versions prior to edge-24.9.3.

This release fixes an error in the CLI in order to allow the linkerd multicluster CLI commands to work correctly even when some of the clusters in a multicluster setup are running releases prior to edge-24.9.3. Additionally, creating a link with linkerd multicluster link --set enableNamespaceCreation=true will allow Linkerd multicluster to create the namespace into which it mirrors services.

edge-24.10.1 (October 3, 2024)

If you’re using Linkerd multicluster, you should consider going straight to edge-24.10.3 to avoid compatibility issues with clusters running versions prior to edge-24.9.3.

edge-24.10.1 introduces native OpenTelemetry support in the (increasing-misnamed) linkerd-jaeger extension: use --set webhook.collectorTraceProtocol=opentelemetry when installing linkerd-jaeger to take advantage of that. For now, the default is still to use the OpenCensus wire protocol, but that’s likely to change in the future.

Additionally, the proxy addresses issue #13023 by setting a 30-second TCP_USER_TIMEOUT on TCP connections to allow Linkerd to do a better job of cleaning up half-open connections (thanks, Vadim Makerov!)

Installing the latest edge release

Installing the latest edge release needs just a single command.

curl --proto '=https' --tlsv1.2 -sSfL https://run.linkerd.io/install-edge | sh

You can also install edge releases with Helm.

Linkerd is for everyone

Linkerd is a graduated project of the Cloud Native Computing Foundation. Linkerd is committed to open governance. If you have feature requests, questions, or comments, we’d love to have you join our rapidly-growing community! Linkerd is hosted on GitHub, and we have a thriving community on Slack, Twitter, and in mailing lists. Come and join the fun!

Linkerd generally does new edge releases weekly; watch this space to keep up-to-date. Feedback on this blog series is welcome! Just ping @flynn on the Linkerd Slack.